Improvement in illuminating apparatus for ovens



H. A. STADLER.

ILLMINATING APPARATUS FOR OVENS.

NO. 190,637. Patented May 8,1877.

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MFETERS. FHOTD LITHOGHAPHER. WASHINGTON. D C.

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HENRY A. srADLER, or NEW Youx, N. Y.

IMPROVEMENT IN ILLUMINATING APPARATUS FOR OVENS.

Specification forming part of Letters Patent No. 190,637, dated May 8, 1877; application tiled April 17,1877.

ously used by chemists in the hoods of their laboratory furnaces, or applied to any inclosure which it is desirable to illuminate, but

i which contains gases or vapors which will not vigorously support the combustion of illuminating material, or which would entirely extinguish the same. 4

There may be several ways of carrying out my invention Withoutmaterially affecting the character of the improvement, and various illuminating materials may be used; but in the example of the invention shown inthe drawing, the description of which will fully illustrate the nature 0fthe invention, I use gas for illumination, which is, where it can be obtained, more convenient than other illuminating materials.

The invention consists partly in a combina tion, with a door for insertion in the side of an oven or inclosure to be illuminated, of a lantern, which, when the door closes, lights lthe interior of the oven,said lantern having draft-holes at 'the bottom and top of the same for the exit of the gases of combustion, and supply of external air to support the combus tion of the illuminating material supplied to the burner, from which is excluded the inter nal atmosphere of the .oven or inclosure by the construction of the lantern.

The invention further consists in the combination,I with the said door and another door for closing the opening .through the door-casing when the lantern-carrying door is opened, of a latch-bar, arranged in such relation with fthe said doors, which open in opposite direc tions,that it holds either of the doors shut by `acting against the front edge of one door and the back edge of the other door.

The invention also consists in the combination, with an oven-door having an attached lantern, of a swing-joint gas-cock, for partially shutting the flow of gas to the burner when said door is opened and the interior of the oven is not required to be lighted.

Figure l in the accompanying drawing represents an outside view of the decreasing with one door closed, and a vertical central -section of the lantern and lantern-carrying door swung outward, as when not in use. Fig. 2 is a section on the line x x in Fig. l, and a view of the inside face of the lantern and lantern-carrying door. Fig. 3 is a horizontal section of the entire apparatus on the line z z in Fig. 1, with the lantern in position to light up the interior of the oven or inclosure it is designed to illuminate. Fig. 4 is a front elevation of the apparatus viewed from the outside, the parts being in the same adjustment as shown in Fig. 3.

A represents vthe door-casing, to which, or to a frame, b, attached to said casio g, is hinged the door C. Or the said door may be fitted to slide in the said casing, as may be preferable for some purposes. The object of said door is to close off communication between the interior and exterior of the oven or inclosure, in 'the side of which the said casing is inserted, at times when it is not desired to illuminate the interior of such oven or inclosl ure, and while the oven is being heated,

may be constructed to slide in said casing.

Whether said lantern-carrying door slides or swings, the lantern is attached to its inner side, so that when said door is alid or swung to close the opening, the lantern. projects into the interior ot' the oven or inclosure to be illuminated.

I do not confine myself to any particular construction of the lantern, except the pro- `vision for supplying external air to support the combustion of the illuminating-llame therein, and the exclusion therefrom ofthe gases or vapors in the oven or inclosure,

which would either diminish or totally extin guish the llame; but I prefer to make its in terior surface, except such portions thereof as are transparent, a reliecting-surface, either by coating the same with polished metals or alloys, or by afxing thereto suitable reflectors. Or I may use both these methods, the reflecting'surfaces being so arranged either adjustably or otherwise, to throw as much light as possible into the oven or inclosure to be illuminatcd.

E is the lantern attached to the door D. It is preferably semcircular in its horizontal cross-section, and it has a transparent face, f, preferably of mica. The said lantern is so tted to the door D that no vapor 0r gas from the interior of the oven or inclosure can enter it to diminish or extinguish the llame, it being tightly closed on the side next the interior of the oven.

VIn the back part of the lantern, at both the bottom and the top of the same, I form a draft passage or passages, hole or holes, h, the lower for the inux ol' pure external atmospheric air, to support the combustion of the illumimating-flame, and the upper for the escape of the heated gases generated by said combustion, the circulation being indicatedY by arrows in Fig. 1.

Reliecting-plates ii' are, respectively, placed near the top and bottom of the interior of the lantern, leaving spaces or tlues between said plates and the top and bottom of the lantern for air circulation. The lower plate t' is perforated at lc, and the upper plate is perforated at k', Fig. l, for the passage of air, said plates directing the ow of air to better support the combustion of the flame.

L represents the burner. When a gasburner is used, I employ a swing-joint gascock, m, to connect the external tubgJ or pipe n, which supplies gas to the burner with the short tube which passes through the door D and connects the pipe fn, with the burner. When the said door D is swung outward the swing-joint gas-cock m abut's against the side of the casing A, as shown in dotted outline in Fig. 3, and turns off the gas, so that it burns very low, (merely with what is known as a tell-tale ilame,) a stop preventing the gas from being wholly extinguished. This construction compels economy by workmen in the use of gas.

Either of the doors is held closed by the latch-bar p, which acts either against the rear edge of the door D, as shown in Figs. 3 and 4, or against the front edge of the door C, as shown in Figs. 1 and 2.

I claiml 1. The combination, with the oven door D, ofthe lantern E, closed toward the interior of the oven, but provided with draft holes or passages for the entrance of external atmospheric air and the exit of the gases of combastion, substantially as and for the purpose specified.

2. The combination, with the door D and the door C, opening in opposite directions, of the latch-bar p, arranged to act against the front edge of one door or the rear edge of the other door, to hold either of said doors closed, substantially as and for the purpose specified.

3. The combination, with the lantern carrying door D andthe door-casing A, of the swingjoint gas-cock m, substantially as and for the purpose set forth.

HENRY A. STADLER..

Witnesses:

BENJAMIN W. HOFFMAN, FRED. HAYNEs. 

